THERMOPLASTIC RESINS CONTAINING PBT UNITS, HAVING REDUCED ORGANIC CARBON EMISSIONS

Description

Field of the Invention

[0001] The invention relates to the field of thermoplastic polymers, particularly thermoplastic polymers containing polybutyleneterephthalate (PBT) repeat units.

Background of the Invention

[0002] Thermoplastic resins having a polybutylene terephthalate (PBT) component, such as PBT itself and copolyetherester elastomers having PBT blocks, are used increasingly as engineering polymers in diverse end uses, including the automotive industry. Such resins may in particular be used in automobile interiors. Copolyetherester elastomers, for example, are widely used in air-bag deployment doors.

[0003] Many thermoplastic resins suffer the disadvantage that moulded articles made from the resins exhibit a phenomenon known as outgassing. Outgassing is the emission of organic molecules of relatively low molecular weight into the surrounding environment. Outgassing is considered disadvantageous because many of the components that are emitted have unpleasant odours, or may be irritants. PBT-containing resins are particularly prone to emit tetrahydrofuran (THF), particularly within the first weeks after moulding. Outgassing is usually worsened if the resin is used under conditions of elevated temperature (i.e. above 100°C). Automobile manufacturers are adopting increasingly strict requirements as regards to outgassing in automobile interiors.

[0004] European patent no. EP 0 683 201 (Polyplastics Co. Ltd.) describes a method for reducing gas (particularly THF) in moulded articles made of PBT. The method involves adding a compound of Formula I, II or III during polymerisation of the monomers to make PBT:

[0005] A need remains for methods for reducing outgassing in PBT-containing thermoplastic resins.

[0006] US 2005 0215 425 deals with the preparation of PBT using a Titanium catalyst. A phosphorous containing ester is used as stabilizer to prevent discoloration. The phosphorous containing ester does not contain free hydroxyl groups and is a phosphite or a phosphorous acid ester and is added after the esterification step and before polymerisation step. Relation between stabilizer and amount of THF released by PBT is mentioned.

[0007] US 3 965 071 describes a deactivation method of Titanium catalysts used for the preparation of polyesters from terephthalic acid and butanediol. The catalyst deactivation takes place after esterification is complete and phosphoric acid or a phosphate ester are used to deactivate the Ti catalyst. Thereafter the PBT is prepared through polymerisation/polycondensation.

Summary

[0008] The invention provides a method or process for reducing outgassing in a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, which resin is made by polymerising monomers in the presence of a titanium catalyst, the method or process comprising the step of: adding to the resin, after polymerisation of the monomers, a titanium catalyst deactivating compound, wherein the titanium catalyst deactivating compound is selected from the group consisting of: 3-(hydroxyphenyl phosphinyl) propanoic acid or a salt thereof, a salt of 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate, and a salt of diethylphosphinic acid.

[0009] The invention further provides a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, the resin further comprising at or about 0.01 to 3 wt% of the compound of Formula IV":

or at or about 0.01 to 3 wt% of sodium 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate.

[0010] Further described herein is a use of a titanium catalyst deactivating compound for reducing outgassing in a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, which resin is made by polymerising monomers in the presence of a titanium catalyst.

[0011] Also described herein is a moulded, extruded or shaped article made from a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, the resin further comprising at or about 0.01 to 3 wt% of the compound of Formula IV":

or at or about 0.01 to 3 wt% phenyl phosphinate, or at or about 0.01 to 3 wt% of a salt (preferably sodium) of 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate.

Detailed Description of Preferred Embodiments

Abbreviations

[0012] 

PBT: polybutylene terephthalate

THF: tetrahydrofuran

PPG: polypropylene glycol

PEG: polyethylene glycol

TOC: total organic carbon emissions

GC-MS: gas chromatography-mass spectrometry

3HPP: 3-(hydroxyphenyl phosphinyl) propanoic acid

[0013] The inventors have surprisingly found that total organic carbon emissions (TOC), and in particular tetrahydrofuran (THF) emissions can be reduced in a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, which resin is made by polymerising monomers in the presence of a titanium catalyst, by adding to the resin, after polymerisation of the monomers, a titanium catalyst deactivating compound. Resins prepared by the method of the invention show a reduction in THF emissions shortly after melt forming.

[0014] Outgassing in the context of the present description refers to the emission of volatile organic substances from a resin, which substances can be detected, for example, according to the method of the Verband der Automobilindustrie [The German Association of the Automotive Industry (VDA)] standard VDA 277. In particular it refers to the emission of THF, which is a particular problem immediately after moulding, extruding or shaping of a resin comprising a PBT repeat unit. THF emissions from a resin may be measured, for example, using gas chromatography, for example with flame ionisation detection, or gas chromatography-mass spectrometry (GC-MS). Even though THF emission from resins decreases within the first few weeks after moulding, extruding or shaping, the emission is perceived as a problem, particularly in the automotive industry, in which car interiors must satisfy rigorous emission standards and smell requirements.

[0015] Thermoplastic resins comprising a PBT repeat unit are made by polymerising monomers (e.g. 1,4-butanediol and a terephthalate diester and/or isophthalate diester) in the melt in the presence of a catalyst, often a titanium catalyst, such as titanium tetra(t-butoxide), used either alone, or in the presence of other metal salt catalysts. With a conventional resin, after polymerisation is complete, the resin is removed from the polymerisation vessel, the resin solidifies, and the titanium catalyst remains in active form in the solid resin at concentrations of from at or about 10 to 1000 ppm titanium (mass titanium to mass polymer). While not wishing to be limited by theory, it is believed that the titanium catalyst can catalyse the formation of outgassing components such as THF when the resin is in the melt, for example on remelting for moulding, extrusion or shaping. By adding a titanium catalyst deactivating compound to the resin comprising a PBT repeat unit, the activity of the titanium catalyst is reduced. It is believed that this results in reduced outgassing of the solidified resin, particularly emission of THF.

[0016] The expression "titanium-catalyst deactivating compound" is meant to encompass all those compounds that when added to an active titanium catalyst result in a decrease of the titanium catalyst's polymerisation activity.

[0017] The expression "after polymerisation of the monomers", is used to describe the point in the process of manufacturing the resin that the titanium catalyst deactivating compound (e.g. a compound of Formula IV, IV' or IV") is added. The expression is meant to encompass any point in time at or about which or after which the condensation polymerisation reaction has resulted in a polymer with the desired molecular weight and viscosity. The desired molecular weight and viscosity are selected to meet the subsequent use requirements of the resin.

[0018] Particular examples of the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit include: PBT, copolyether ester elastomers having PBT segments, co-PBT's (i.e. PBT's in which some of the 1,4-butane diol is replaced with, for example, one or more other diols, such as aliphatic, cycloaliphatic (for example 1,4-cyclohexanedimethanol), or aromatic diols (for example 2,2-bis[4-(hydroxyethoxyphenyl)]-propane as disclosed in US patent no. 4,066,607, incorporated herein by reference) or the terephthalate group is replaced by the residue of other diacids such as isophthalic acid or adipic acid (as disclosed, for example, in US patent no. 4,131,595), and blends of any of these. Particularly preferred are PBT and copolyether ester elastomers having PBT segments, such as those available under the tradenames Hytrel® (Dupont), Arnitel® (DSM) and Riteflex® (Ticona).

[0019] The titanium catalyst deactivating compound is a compound of the general Formula IV, or salts thereof:

selected from the group consisting of:

3-(hydroxyphenyl phosphinyl) propanoic acid ("3HPP"; compound of Formula IV") or a salt thereof, preferably used at or about 0.05 to 0.8 wt%, more preferably at or about 0.1 to 0.5 wt%:

a salt (preferably sodium) of 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate, preferably used at at or about 0.01 to 3 wt%, more preferably at or about 0.05 to 0.5 wt%:

and

salts of diethylphosphinic acid, in particular the aluminium salt (aluminium tris-diethylphosphinate), preferably used at at or about 0.01 to 1 wt%, more preferably at or about 0.05 to 0.5 wt%

[0020] In a particularly preferred embodiment of the method or process of the invention, the titanium catalyst deactivating compound that is used is a compound of Formula IV" (3HPP):

or a salt (preferably sodium) of 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate, or the aluminium salt of diethyl phosphinic acid.

[0021] The method or process of the invention involves adding a titanium catalyst deactivating compound as defined above to the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit in the melt. Since the titanium catalyst deactivating compound deactivates the titanium catalyst, it is added after polymerisation of the PBT monomers is complete. This may be done immediately after polymerisation (i.e. by direct addition to the polymer melt in the polymerisation vessel, once the polymerisation process has reached the desired stage). Alternatively, the titanium catalyst deactivating compound may be added in a separate process by remelting granules of the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit and adding the titanium catalyst deactivating compound. In yet another embodiment of the invention, the polymerised resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit may be fed to a separate mixing apparatus (such as a single or twin-screw compounding extruder) immediately after polymerisation, for mixing with the titanium catalyst deactivating compound. The outgassing reduction is more efficient the greater the effectiveness of the mixing of the resin and the titanium catalyst deactivating compound. Preferably, the mixing of the resin and the titanium catalyst deactivating compound should be continued until the titanium catalyst deactivating compound is homogeneously distributed in the resin.

[0022] The titanium catalyst deactivating compound as defined above is usually added in a number of moles that is at least approximately stoichiometric to the number of moles of titanium catalyst that were used in the polymerisation of the resin. The titanium content (ppm in terms of mass of titanium per mass of polymer) is known from the amount of catalyst added at the start of polymerisation. Alternatively, it may be determined by analysing the resin, for example, by X-ray fluorescence (XRF) or atomic emission or absorption spectroscopy. In most cases, the titanium catalyst is present in an amount of at or about 10 to 1000 ppm (i.e. approximately 0.2 to 21 moles Ti per 1000 kg resin), commonly in the range of at or about 100 to 400 ppm (i.e. approximately 2 to 8 moles Ti per 1000 kg resin). In a preferred embodiment, the catalyst deactivating compound as defined above is added in an amount of at or about 0.5 to 20 equivalents (phosphorus atoms:titanium atoms), more preferably at or about 1 to 10 equivalents. For the titanium catalyst deactivating compounds as defined above, this works out to an amount of at or about 0.01 to 2 wt% with respect to the resin, more preferably at or about 0.05 to 1 wt% with respect to the resin.

[0023] Testing the resulting resin for outgassing may be done by a number of techniques. An example of a technique that may be used to evaluate total organic carbon emissions from a resin is described in the Verband der Automobilindustrie [The German Association of the Automotive industry (VDA)] standard VDA 277.

Example 1

[0024] Hytrel® 5556 is a copolyetherester elastomer available from DuPont. It has a nominal hardness of 55 Shore D and comprises hard segments of PBT with soft segments of polyether terephthalate and contains a titanium based catalyst at approximately 100 to 400 ppm (mass Ti to mass polymer; i.e. approximately 2 to 8 moles Ti per 1000 kg resin). For this experiment the batch used had a titanium content of approximately 150 ppm.

[0025] Hytrel® 5556 has a typical Melt Flow Rate (MFR) of approximately 7.5 g/10min when measured to ISO1133 at 220°C and with a load of 2.16 kg.

[0026] The Hytrel® 5556 was melt compounded in a twin screw extruder with various levels of compounds of general Formula IV as listed in Table 1. The control resin was Hytrel® 5556 put through the same compounding process but without the addition of a compound of Formula IV.

[0027] The inventive and control resins were injection moulded into bars of approximate overall dimensions of 75 mm X 12.5 mm X 2 mm, and of the form described as Test Specimen type 5A in the International Standard ISO 527-2: 1993(E). Immediately after moulding the bars were sealed in aluminium-lined polyethylene envelopes. The sealed envelopes maintain THF-content at approximately the level immediately after moulding until analysis can de done. For analysis, the bars were removed from the envelopes and cut into four pieces and placed in septum-sealed vials. The control sample and inventive samples were treated in exactly the same fashion throughout the sample preparation process.

Total organic carbon emissions (TOC)

[0028] The vials containing the control and the inventive sample were heated for approximately 5 hours at 120°C. The "headspace" above the resin samples (i.e. the air space in the vials above the resin) was sampled, and injected into a gas chromatograph according to VDA 277. Detection was with a flame ionisation detector. The area under the peaks for the inventive sample was compared to the area under the peaks for the control, and the results reported as %TOC of control. The results are reported in Table 1 as "%TOC".

[0029] It is clear from the results reported in Table 1 that the addition of a compound of Formula IV to a PBT-block-containing resin results in reduction of total organic carbon emissions.

THF emissions

[0030] Control and inventive samples were prepared as above. The vials containing the control and the inventive sample were heated for approximately 5 hours at 120°C. The "headspace" above the resin samples (i.e. the air space in the vials above the resin) were sampled, and injected into a gas chromatograph. Detection was with flame ionisation detection (mass spectrometry may also be used). The area under the peak for THF for the inventive sample was compared to the area under the peak for THF for the control, and the results reported as %THF of control. The results are reported in Table 1 as "%THF".

[0031] It is clear from the results reported in Table 1 that the addition of a compound of Formula IV to a PBT-block-containing resin results in reduction of THF emissions.

Example 2

[0032] Crastin® 6131 is a PBT resin available from DuPont. It has an average melt flow rate (MFR) of 48 g/10 mins, ISO1133, 250°C, 2.16 kg and contains a titanium-based catalyst, at approximately 100 ppm (mass Ti to mass polymer; i.e. approximately 2 moles Ti per 1000 kg resin).

[0033] The Crastin® 6131 was melt compounded in a twin screw extruder with various levels of compounds of general Formula IV as listed in Table 2. The control resin was Crastin® 6131 put through the same compounding process but without the addition of a compound of Formula IV.

[0034] The inventive and control resins were injection moulded into plates of dimensions 80 x 80 x 3mm. Immediately after moulding the bars were sealed in aluminium-lined polyethylene envelopes. The sealed envelopes maintain THF-content at approximately the level immediately after-moulding until analysis can de done. For analysis, the plates were removed from the envelopes and cut into pieces of approximately 4 x 4 x 3mm. Approximately 1.5 g of these granules were placed in a septum-sealed vial. The control sample and inventive sample were treated in exactly the same fashion throughout the sample preparation process.

Total organic carbon emissions (TOC)

[0035] Total organic carbon emissions were measured as above. The results are reported in Table 2 as "%TOC".

[0036] It is clear from the results reported in Table 2 that the addition of a compound of Formula IV to PBT results in reduction of total organic carbon emissions.

THF emissions

[0037] THF emissions were measured as above. The results are reported in Table 2 as "%THF".

[0038] It is clear from the results reported in Table 2 that the addition of a compound of Formula IV to a PBT-block-containing resin results in reduction of THF emissions.

Example 3

[0039] The procedure of example 2 was followed using, in place of the Crastin® 6131, a PBT resin with an average melt flow rate (MFR) of 48 g/10 mins, ISO1133, 250°C, 2.16 kg and containing a titanium-based catalyst, at approximately 170 ppm (mass Ti to mass polymer; i.e. approximately 3.5 moles Ti per 1000 kg resin).

[0040] The results obtained are reported in Table 3

Table 1. TOC (%TOC; total organic carbon emissions) and THF emissions (%THF) for PBT-block containing copolyether ester elastomer resin (Hytrel®5556) containing a compound of Formula IV, as a percentage of values for control resins without the compound of Formula IV
Compound of Formula IV	Approximate molar ratio of P:Ti	%TOC	%THF
Sodium phenyl phosphinate *
0.075 wt%	1.4	49	37
0.15 wt%	2.8	73	59
0.3 wt%	5.6	92	74
Sodium hypophosphite *
0.05 wt%	1.5	48	29
0.1 wt%	2.9	54	34
0.2 wt%	5.9	47	35
3HPP
0.2 wt%	2.9	35	22
0.4 wt%	5.7	44	34
Disodium hydrogen phosphate (anhydrous)*
0.13 wt%	2.8	62	47
VictastabHMP *
0.33 wt%	2.7	62	25
Monosodium dihydrogen phosphate *
0.11 wt%	2.8	78	58
Sodium 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate
0.1 wt%	0.6	35	23
0.25 wt%	1.6	57	44
Aluminium tris-diethylphosphinate
0.1 wt%	2.5	35	21
0.25 wt%	6.1	44	30

* not according to the invention

Table 2 TOC (%TOC; total organic carbon emissions) and THF emissions (%THF) for PBT resin (Crastin®6131) containing a compound of Formula IV, as a percentage of values for control resins without the compound of Formula IV

Compound of Formula IV	Approximate molar ratio of P:Ti	%TOC	%THF
3HPP
0.1 wt%	3.2	65	62
0.3 wt%	9.6	67	62
Monosodium dihydrogen phosphate *
0.1 wt% P:Ti 5,7	5.7	85	82
0.3wt% P:Ti 17	17	75	72

* not according to the invention

Table 3 TOC (%TOC; total organic carbon emissions) and THF emissions (%THF) for PBT resin described in Example 3 containing a compound of Formula IV, as a percentage of values for control resins without the compound of Formula IV

Compound of Formula IV	Approximate molar ratio of P:Ti	%TOC	%THF
3HPP
0.2 wt%	2.6	50	49
0.4 wt%	5.3	49	48

Claims

1. A method for reducing outgassing in a resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, which resin is made by polymerising monomers in the presence of a titanium catalyst, the method or process comprising the step of:

adding to the resin, after polymerisation of the monomers, a titanium catalyst deactivating compound, wherein the titanium catalyst deactivating compound is selected from the group consisting of: 3-(hydroxyphenyl phosphinyl) propanoic acid or a salt thereof, a salt of 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate, and a salt of diethylphosphinic acid.

2. The method of claim 1, wherein the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit is selected from PBT, copolyether ester elastomers having PBT segments, co-PBT's, and blends of any of these.

3. The method of claim 1, wherein the titanium catalyst deactivating compound is 3-(hydroxyphenyl phosphinyl) propanoic acid, sodium 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate, or the aluminium salt of diethylphosphinic acid.

4. The method of claim 1, wherein the titanium catalyst deactivating compound is added to the resin at a concentration or 0.01 to 2 wt%.

5. The method of claim 1, wherein the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit is a copolyether ester elastomer, or wherein the resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit is PBT.

6. A resin comprising at least one component having a polybutylene terephthalate (PBT) repeat unit, the resin further comprising 0.01 to 3 wt% of the compound of Formula IV":

or 0.01 to 3 wt% of sodium 2,2'-methylenebis-(4,6-di-tert-butylphenyl)phosphate.

7. The resin of claim 6, wherein the at least one component having a polybutylene terephthalate (PBT) repeat unit is selected from PBT, copolyether ester elastomers having PBT segments, co-PBT, and blends of any of these.

8. The resin of claim 6, wherein the at least one component having a polybutylene terephthalate (PBT) repeat unit is a copolyether ester elastomers having PBT segments, or wherein the at least one component having a polybutylene terephthalate (PBT) repeat unit is PBT.

9. The resin of claim 6, comprising 0.01 to 3 wt% of the compound of Formula IV":

Ansprüche

1. Methode zum Reduzieren des Ausgasens bei einem Harz, das mindestens eine Komponente umfasst, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, welches Harz durch Polymerisieren von Monomeren in Gegenwart eines Titankatalysators hergestellt wird, wobei die Methode oder das Verfahren den Schritt umfasst des:

Zugebens zu dem Harz, nach der Polymerisierung der Monomere, einer Titankatalysator-deaktivierenden Verbindung, wobei die Titankatalysator-deaktivierende Verbindung aus der Gruppe ausgewählt ist, bestehend aus: 3-(Hydroxyphenylphosphinyl)propionsäure oder einem Salz davon, einem Salz von 2,2'-Methylenbis-(4,6-di-tert-butylphenyl)phosphat und einem Salz von Diethylphosphinsäure.

2. Methode nach Anspruch 1, wobei das Harz, das mindestens eine Komponente umfasst, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, unter PBT, Copolyetheresterelastomeren, die PBT-Segmente aufweisen, Co-PBT und Mischungen von beliebigen von diesen ausgewählt wird.

3. Methode nach Anspruch 1, wobei die Titankatalysator-deaktivierende Verbindung 3-(Hydroxyphenylphosphinyl)propionsäure, Natrium-2,2'-methylenbis-(4,6-di-tert-butylphenyl)phosphat oder das Aluminiumsalz von Diethylphosphinsäure ist.

4. Methode nach Anspruch 1, wobei die Titankatalysator-deaktivierende Verbindung dem Harz in einer Konzentration von 0,01 bis 2 Gew.-% zugegeben wird.

5. Methode nach Anspruch 1, wobei das Harz, das mindestens eine Komponente umfasst, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, ein Copolyetheresterelastomer ist oder wobei das Harz, das mindestens eine Komponente umfasst, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, PBT ist.

6. Harz, umfassend mindestens eine Komponente, die eine Polybutylenterephthalat-(PBT-) Wiederholungseinheit aufweist, wobei das Harz des Weiteren 0,01 bis 3 Gew.-% der Verbindung der Formel IV":

oder 0,01 bis 3 Gew.-% Natrium-2,2'-methylenbis-(4,6-di-tert-butylphenyl)phosphat umfasst.

7. Harz nach Anspruch 6, wobei die mindestens eine Komponente, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, unter PBT, Copolyetheresterelastomeren, die PBT-Segmente aufweisen, Co-PBT und Mischungen von beliebigen von diesen ausgewählt wird.

8. Harz nach Anspruch 6, wobei die mindestens eine Komponente, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, ein Copolyetheresterelastomer ist, das PBT-Segmente aufweist, oder wobei die mindestens eine Komponente, die eine Polybutylenterephthalat- (PBT-) Wiederholungseinheit aufweist, PBT ist.

9. Harz nach Anspruch 6, umfassend 0,01 bis 3 Gew.-% der Verbindung der Formel IV":

Revendications

1. Procédé de réduction du dégagement de gaz dans une résine comprenant au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT), laquelle résine est fabriquée par polymérisation de monomères en présence d'un catalyseur à base de titane, le procédé ou le processus comprenant l'étape de:

addition à la résine, après la polymérisation des monomères, d'un composé de, dans lequel le composé de désactivation du catalyseur à base de titane est sélectionné dans le groupe constitué de : l'acide 3-(hydroxyphényl phosphinyl) propanoïque ou un sel de celui-ci, le 2,2'-méthylènebis-(4,6-di-tert-butylphényl)phosphate, et un sel d'acide diéthylphosphinique.

2. Procédé selon la revendication 1, dans lequel la résine comprenant au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est sélectionnée parmi le PBT, les élastomères de copolyéther ester ayant des segments PBT, les co-PBT, et les mélanges de n'importe lesquels d'entre eux.

3. Procédé selon la revendication 1, dans lequel le composé de désactivation de catalyseur à base de titane est l'acide 3-(hydroxyphényl phosphinyl) propanoïque, le 2,2'-méthylènebis-(4,6-di-tert-butylphényl)phosphate de sodium, ou le sel d'aluminium de l'acide diéthylphosphinique.

4. Procédé selon la revendication 1, dans lequel le composé de désactivation de catalyseur à base de titane est ajouté à la résine à une concentration de 0,01 à 2 % en pds.

5. Procédé selon la revendication 1, dans lequel la résine comprenant au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est un élastomère de copolyéther ester, ou dans lequel la résine comprenant au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est le PBT.

6. Résine comprenant au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT), la résine comprenant en outre 0,01 à 3 % en pds du composé de formule IV":

ou 0,01 à 3 % en pds de 2,2'-méthylènebis-(4,6-di-tert-butylphényl)phosphate de sodium.

7. Résine selon la revendication 6, dans laquelle le au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est sélectionné parmi le PBT, les élastomères de copolyéther ester ayant des segments PBT, les co-PBT, et les mélanges de n'importe lesquels de ceux-ci.

8. Résine selon la revendication 6, dans laquelle le au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est un élastomère de copolyéther ester ayant des segments PBT, ou dans laquelle le au moins un composant ayant une unité de répétition poly(téréphtalate de butylène) (PBT) est le PBT.

9. Résine selon la revendication 6, comprenant 0,01 à 3 % en pds du composé de formule IV":